I bought this blush brush from Real Techniques a month ago and have never gone back since!
The bristles are ultra soft, but distribute product so well. I find it easier to build up colour using this, but it seems physically impossible to apply too much product with it. Probably due to the nature of how soft the bristles are it helps apply a light colouring without going over board with the streaky of rosie look.
Have you tried it? And if you have, what do you think of it?
Available from Boots.